In recent years, with the sophistication of wireless communication due to the popularization of new technologies including long term evolution (LTE), smaller cells are increasingly widespread in order to reduce network load. In particular, a femto base station that forms a femtocell that is a hundred-thousandth of a macrocell is rapidly increasing; however, because the femto base station has similar functions as those of a macro base station, the equivalent maintenance and management as those of the macro base station are needed. However, the number of installed femto base stations is much larger than the macro base stations; therefore, in the femto base stations, an Internet-based interface (for example, technical report (TR)-069) rather than a dedicated line is employed in order to suppress maintenance and management cost. Specifically, in a network formed by femtocells, a monitoring device, such as an equipment management system (EMS), monitors under-controlled femto base stations in real time via the above described interface.
Patent Document 1: Japanese Laid-open Patent Publication No. 2013-26794
Patent Document 2: Japanese Laid-open Patent Publication No. 2004-145781
Patent Document 3: Japanese Laid-open Patent Publication No. 2009-231861
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Patent Document 5: Japanese Laid-open Patent Publication No. 2011-66522
However, because the number of the femto base stations to be monitored is large, large load is constantly applied to the monitoring device regardless of occurrence or non-occurrence of faults in the femto base stations. Specifically, the monitoring device needs about one second for a connection sequence and a disconnection sequence in order to monitor a single femto base station. Therefore, if 100,000 femto base stations are to be monitored with a period of 30 seconds for example, the monitoring device needs to have the capability to simultaneously monitor 3,000 or more femto base stations. Further, the monitoring device performs monitoring by checking connections to the femto base stations. Therefore, it is difficult to determine whether the monitoring target femto base stations are in fault states or in power disconnected states, or it is difficult to determine whether a fault is an intermittent fault or a permanent fault.